Nodes in a communications network may be divided into a source node, a destination node, and an intermediate node according to their functions. The source node is a node serving as a source for sending service data, the destination node is a node serving as a sink for receiving the service data, and the intermediate node is a node for forwarding the service data. In other words, the node to which service data is added may be called the source node, and the node at which the service data is dropped may be called the destination node. The communications network mainly includes a data communications network of an upper layer and a transport network of a lower layer. The communications network may be divided into a core network and a convergence network according to network topology structures, where a node located in the core network may be called a core node, and a node in the convergence network may be called an edge node. The core node mainly includes a core router in the data communications network of the upper layer, and a wavelength add/drop multiplexing device in the transport network of the lower layer. The edge node mainly includes an edge router in the data communications network of the upper layer, and a wavelength add/drop multiplexing device in the transport network of the lower layer. For example, the edge node and the code node in the communications network may respectively serve as the source node and the destination node when a service is added or dropped, and may serve as the intermediate node when no service is added or dropped. In the communications network, usually, the edge node serves the source node and the destination node, and the core node serves the intermediate node. As wideband services are developed and the number of wideband users increases, the network flow in the communications network exponentially increases, so that requirements on capacity and power consumption of the router in the node become increasingly higher. Currently, in order to support the transfer of the service data in the communications network, the capacity and the power consumption of the router have been developed to an unendurable extent, and the capital costs and operational costs are high. Therefore, it is a problem to be solved urgently how to reduce the capacity and the power consumption of the router in the node, that is, to reduce the capacity and the power consumption of the node, especially, the power consumption of the node.
In view of the problem, a solution is proposed in a first prior art. According to the first prior art, in the communications network, the node, especially, the core node, a wavelength cross-connection device or an Optical Transport Network (OTN) cross-connection device is adopted to replace the original wavelength add/drop multiplexing device. In the solution, when passing the node, the service data which is not locally dropped directly passes through a wavelength layer or an Optical Demultiplexer Unit (ODU) layer. As the electrical processing efficiency of the wavelength cross-connection device or the OTN cross-connection device of the node is high, the power consumption of the node, especially, the power consumption of the core node may be reduced in a certain degree in the technical solution of the first prior art.
In view of the problem, another solution is proposed in a second prior art, that is, an all-optical switching technology, for example, an Optical Burst Switching (OBS) technology. The main concept of the OBS technology is that Optical Burst (OB) paths and a control channel are physically separated, OB data and the control channel are respectively transferred, the node only performs an electrical process on the control channel, and reserves, according to information carried in the control channel, resources for the OB data being at hand, so that when passing the node, the OB data may be directly transferred and switched on the optical layer without an optical-to-electrical conversion, thereby simplifying an electrical processing procedure of the node, and reducing the power consumption of the node.
However, in the implementation of the present invention, the inventor finds that the prior art has at least the following problems.
In the technical solution of the first prior art, the granularity of the service data is large when passing through the wavelength layer or the ODU layer on the node, so that a bandwidth is excessively large when the nodes are connected by using the wavelength or the ODU path. When the nodes are connected by using the wavelength or the ODU path, it is equivalent to providing a direct path between the nodes, especially, the edge nodes. The number of the paths approximately has a square relation with the number of the nodes, and the square relation is as follows: n*(n−1)/2, where n is the number of routers in the node. When the node needs to be connected to more nodes, the number of the required paths is enormous, the number of the required connections is increased, and the node needs to provide more ports for connecting to more nodes, so that the volume, the power consumption, and the costs of the node are increased.
In the second prior art, although the power consumption of the node is reduced, the OBS lacks appropriate optical buffers, and thus a data conflict may easily occur on the optical layer when the data is transmitted in the OBS system.